Daisy sadly comes a cropper in this dismal revival of Denise Deegan's ripping yarn, which conjures up an Angela Brazil-style world of midnight feasts, morning dips, dormy fights, nail-biting hockey matches and class bullies, as well as hidden treasure, a daring clifftop rescue, a mysterious Russian emigre and a long-lost father.

It's 1927, and Daisy Meredith (Lucy Austin) is the poor-but-clever elementary school pupil who thinks it would be absolutely topping to learn Latin and Greek at Grangewood School for Young Ladies – "the jolliest school in England". But when she wins a scholarship and arrives there, she faces the fearful ­machinations of the class rotters, the snobby Sybil Burlington (Fiona Domenica) and her toadying friend Monica (Jennifer Page). We know they are rotters because they don't like games.

Despite the Latin tags and cries of "jubilate", this ain't Tom Stoppard. But in the right hands, Deegan's pitch- perfect spoof is still gloriously funny entertainment, which explains its ­previous form in the West End, including a three-year run. But the trick is to play it absolutely straight so that the tongue can't be seen poking out of the cheek.

Nadine Hanwell's production offers a variety of conflicting playing styles, and although it may have burst out of its gymslip in the tiny Baron's Court theatre, here it is so lacking in energy that it is in urgent need of a dose of matron's cod liver oil. To use the favourite phrase of the beautiful, firm but fair head girl, Clare Beaumont: "Buck up, kiddies."

The timing is all askew, so many of the funniest lines are simply thrown away. Some of the cast might well shine in other circumstances, but they are constrained by a pedestrian production that lacks basic stagecraft. Instead of offering irrepressible entertainment, it feels like two-and-a-half hours of extra prep.